Yttrium-90: Application in Nuclear Medicine and Production in Radionuclide Generators

Yttrium-90 is a promising therapeutic radionuclide for nuclear medicine with wide application in radiotherapy of liver cancer and metastases by means of transarterial radioembolization using polymer and glass microspheres, as well as in the treatment of rheumatoid arthritis and osteoarthritis with [90Y]yttrium citrate colloids. Low-specific-activity 90Y, available from research nuclear reactor via 89Y(n,γ)90Y reaction, suits well for these purposes. In recent years, great interest has been focused on highly specific radiopharmaceuticals (RPs) labeled with 90Y for peptide-receptor radiotherapy, radioimmunotherapy, and radioligand radiotherapy. Syntheses of the RPs requires 90Y of high specific activity, produced in 90Sr/90Y isotope generators. The parent radionuclide 90Sr is readily available as the main component of nuclear fuel waste. This review examines the main approaches to developing different types of generators using extraction, sorption, and electrochemical methods, as well as their combinations. It also provides an overview of the main classes of 90Y-based radiopharmaceuticals used in targeted radionuclide therapy for various tumors.